After making twice-monthly stops in Westminster since September, the mission started the new year with weekly visits to the Human Services Programs building on Distillery Drive.

"Westminster is our busiest stop," said Lisa Bailey, a registered nurse, who volunteers at the mission once a month. "We always have patients here. For many, this is probably the only health care they get."

The mission, founded by Drs. Michael and Gianna Sullivan, is supported through private donations. It arrives in the city just before 9 a.m. every Wednesday and remains at the HSP loading dock until 4 p.m.

On Tuesdays, the clinic alternates between its home base at St. Joseph Catholic Church in Emmitsburg and Brunswick, both in Frederick County.

In Westminster, the staff sees about 35 patients a day in the van that has been converted into two examining rooms, a lab and a waiting room.

With two physicians, a pharmacologist, a lab technician and two registered nurses in attendance, the mission has staff, time and space to care for about 10 more each day.

"Patients are so happy to come on board and be relieved of whatever ailment," said Dr. Gianna T. Sullivan, staff pharmacologist.

For patients such as Leona Williams, the clinic is a blessing on wheels. Uninsured and unable to pay for regular medical care and prescriptions, Ms. Williams, 57, was living with constant pain from rheumatoid arthritis.

"You have to be a sufferer to know the pain," said Ms. Williams. "There is medicine but you can't take it unless you see a doctor regularly."

She saw the clinic's notice in the newspaper and made an appointment. After three visits and free medication, she has "noticed great results." As she left the mission van yesterday, she smiled and gently shook the nurse's hand without wincing.

"This has been a real blessing for me," she said.

Nicole Myers, 19, came to the clinic for advice. She had been awake most of the night with her crying baby.

"She has a regular pediatrician, but, for something like this, I couldn't afford to go," she said.

Mother and 5-month-old daughter left with nose drops, Tylenol and the reassurance that all was well.

"Everybody was so nice," said Ms. Myers. "We will come back."

Many patients return, often to deliver good news, said Dr. Gianna Sullivan.

"People who come here are like a family to us," she said. "One woman stopped in today just to tell us she got a job."

"One man lives in a Dumpster in Westminster," she said. "Another waited in an emergency room five hours and finally came to us for help."

The staff keeps medical records on each patient and often can help connect people with available community services. The mission is working with Carroll County General Hospital to arrange follow-up care, for instance.

"We need some referral program, when a patient needs X-rays or lab studies," said Dr. Gianna Sullivan. "The hospital is reaching out to be a partner with us. Our patients can't pay and the hospital understands that." The partnership, still in the planning stage, could become a model, which "we would like to develop in every community."

Gill Chamblin, Carroll County General Hospital spokeswoman, said, "We'll provide diagnostic services as well as treatment and therapeutic procedures" for patients identified as referrals from the mission.

Dr. Michael Sullivan has courtesy privileges at the Westminster hospital.

"If something happens, he can get in there and work with the patient," said Dr. Gianna Sullivan. "This is just another of the good fruits that come with working in the community."

The mission, which operates solely on donations, hopes to add another weekday to its itinerary by summer.

Since the couple began the work, volunteers have overwhelmed them with offers to help. They draw from a pool of 40 nurses and technicians.

"Here I feel appreciated," said Angel Cruz, a lab technician. "I want to do more but many others also want to donate their time. For me, it is more generous to let others have this experience, too."